The Thomas A. Edison Papers Digital Edition

These documents cover the years 1878-1924, with most of the items dating from 1878-1879. Included are letters from Edison to Clarence J. Blake, an ear specialist and acoustic researcher who had been involved with Alexander Graham Bell on phonautograph experiments. Some of the letters relate to Edison's early work on the phonograph and to the fire at the West Orange laboratory complex in 1914. In one letter Edison refers to himself as "the busiest man in America." Also included is a printed page containing a portion of an address on Edison's phonograph, which was read before American Philosophical Society by Persifor Frazer on April 15, 1878. Inscribed on the page is a note from Edison to Blake. In addition, there are pages from an 1878 laboratory notebook regarding Blake's examination of phonograph tracings of consonant sounds.

The other documents consist of an 1895 letter from Edison to psychologist Hugo Münsterberg enclosing a donation for the Helmholtz Memorial; and a 1924 memorandum by Edison directing Jeffrey P. Buchanan, the manager of disc record manufacturing, to "lay the chemist off & thereby reduce our expenses."